Field
One or more embodiments relate to a positive active material, a lithium battery including the positive active material, and a method of manufacturing the positive active material.
Description of the Related Art
A lithium secondary battery uses an organic electrolyte aqueous solution, and accordingly has high discharge voltage that is at least two times as large as that of a conventional battery using an alkali aqueous solution. Thus, the lithium secondary battery has high energy density.
The lithium secondary battery includes a material capable of intercalating and deintercalating lithium ions, as an active material for negative and positive electrodes. In addition, the lithium secondary battery is manufacturing by charging an organic electrolyte aqueous solution or a polymer electrolyte aqueous solution, which is interposed between the positive electrode and the negative electrode. The lithium secondary battery manufactured thereby generates electrical energy by oxidation and reduction occurring when lithium ions are intercalated and deintercalated at the positive and negative electrodes.
As a positive active material for the lithium secondary battery, LiCoO2 is currently the most widely used. However, a manufacturing cost of LiCoO2 is expensive, and a stable supply of LiCoO2 is not guaranteed. Therefore, as an alternative to such a positive active material, a composite material formed in a combination with nickel (Ni) or manganese (Mn) is being developed.
In the case of a Ni-based oxide composite, in order to increase capacity per unit volume of the Ni-based oxide composite, an amount of Ni of the Ni-based oxide composite may be increased, or a mixture density of the electrode active material may be increased. However, a positive active material that may increase a packing density and satisfy thermal stability and capacity properties at the same time is still needed.